One common theme is growth. Baki is often on a journey of self - improvement in his fighting skills, and Kozue is there to support him. So, many fanfics show how their relationship evolves as Baki grows stronger.
One popular 'baki x kozue fanfic' is 'The Journey of Baki and Kozue'. It focuses on their relationship development in a more adventure - based setting, with Baki's strength and Kozue's supportiveness being key elements.
One popular 'baki fanfic' story could be those that focus on the intense training sessions of the characters in more detail. For example, a fanfic might explore how Baki further hones his martial arts skills in a secluded dojo, facing challenges that were not shown in the original series.
One common theme is friendship. Their relationship often starts as a simple acquaintance and then develops into a deep friendship that they rely on in difficult times. For example, in many fanfictions, they help each other out during battles or challenges.
A crossover with 'Dragon Ball' could also be exciting. Imagine Baki in the Dragon Ball universe, training with Goku or Vegeta. Baki's martial arts skills could be enhanced in the hyper - gravities of Planet Namek or in the Hyperbolic Time Chamber. He could also participate in the World Martial Arts Tournament against Saiyans and other powerful fighters.
First, you need to have a good understanding of the 'baki' universe. Know the characters, their abilities, and their personalities. For example, Baki is known for his tenacity in fighting. Then, come up with an interesting concept. It could be a new adventure for Baki or a different take on an existing storyline.